1. Field of the Invention
The present invention relates to a method for making a cylindrical heat dissipating tube, and more particularly to a method for making a heat dissipating tube for use with an integrated circuit board.
2. Description of Related Art
Because the operating speed of integrated circuits has constantly increased, large integrated circuits have been developed. Moreover, to reduce fabrication cost, the integrated circuits are small in size and a lot of peripherals are integrated to form an even more compact package, such as SOC (System On A Chip) or SOAC (System On An Application Chip). However, large integrated circuits force electronic manufacturers to deal with the heat generated during the operation of the integrated circuit and the associated problems. Tests have shown that the operation of an integrated circuit is adversely affected when the temperature of the integrated circuit reaches 70xc2x0 C. Therefore, electronic manufacturers have been forced to solve the heat problem. To maintain the high speed operation of integrated circuits without interference from heat, heat sinks were introduced to electronic design to lessen the problem. Heat sinks do have the ability to ease the heat problem. However, in practice, the intense heat is created only when the integrated circuit is in operation and is generated within a very short period of time. Therefore, heat sinks are only marginally effective in dissipating such a large amount of heat.
To enhance the heat dissipation, a cylindrical heat dissipating tube is incorporated with the heat sink so that a large amount of heat can be dissipated quickly.
With reference to FIGS. 5 and 6, a fan (94) and a conventional metallic cylindrical heat dissipating tube (90) are mounted on a substrate (92) so that the substrate (92) is able to be mounted on top of an integrated circuit (not shown) to instantly dissipate heat. A heat sink (96) with a channel (not numbered) defined to fit around the conventional heat dissipating tube (90) may be used to increase the heat dissipation capability of the conventional heat dissipating tube (90). The heat dissipating tube (90) is comprised of a cylinder (900) that has two ends that are normally closed by melting and pulling the tube, which forms pointed ends (not shown). A heat dissipating tube (90) with two pointed ends is not suitable for engaging with the substrate (92) to have the desired heat dissipation effect. To obviate the foregoing drawback, the heat dissipating tube (90) is first made of a hollow cylinder (900) with two open ends, and a cap (902) is then soldered in one open end to close the end of the cylinder (900). After one open end is closed, the cylinder (900) is filled with a fluid as a heat conducting medium. Then, another cap (902) is soldered in the other end to close the cylinder (900). However, during the soldering process, a solder line (904) is formed at the joint between the cylinder (900) and the cap (902). The solder line (904) is an obstacle to the transfer of heat to the fluid inside the heat dissipating tube (90). Furthermore, because the fluid is inside the heat dissipating tube (90) and functions as a heat conducting medium, the heat absorbed by the fluid may not conduct and dissipate evenly to the environment. For example, a situation is likely to occur where the temperature at the bottom of the heat dissipating tube (90) is higher than the temperature at the top of the heat dissipating tube (90).
To overcome the shortcomings, the present invention provides an improved method for making a heat dissipating tube to mitigate and obviate the aforementioned problems.
The primary objective of the invention is to provide a method for making a heat dissipating tube that will reduce the cost of making the tube and increase the heat dissipation effect of the tube.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.